Hall’s kick, which came with five seconds left in the first round of their opening-round bout, caused those in the arena to explode with excitement, shock and awe at the powerful and instantaneous knockout. That soon turned to quiet concern for Cella, who was taken to the hospital for precautionary purposes.

"It's one of those ones you want to celebrate but you don't,” White said when he went to the locker room to congratulate Hall on the win. “I guess we know who's winning the $25,000 for knockout. You guys better start going for fight or submission.”

The UFC gives out bonuses at the end of the season for best knockout, best fight and best submission for the entire show.

Before Hall’s devastating knockout, he and Cella had an entertaining fight. Cella landed several big strikes, but Hall had the better of the striking by mixing in knees and pushkicks. Twice Hall knocked down Cella, albeit briefly each time, with kicks to the midsection.